[PATCH v2 2/3] video: rockchip: rk3328: filter unsupported modes

[Matwey V. Kornilov]

You say that the 4K works in Linux. Wouldn't it be better to fix the 4K
support in u-boot?

пн, 24 мар. 2025 г., 01:51 Vasily Khoruzhick <anarsoul at gmail.com>:

> While RK3328 is capable of 4K resolutions, dw-hdmi driver in u-boot
> seems to have some issue with 4K. 1440p or lower works fine.
>
> Limit max resolutions to 2560x1440x60Hz, by filtering the modes with
> pixel clock > 297MHz
>
> Fixes: f3ea872970d603 ("video: rockchip: Add rk3328 hdmi support")
> Signed-off-by: Vasily Khoruzhick <anarsoul at gmail.com>
> ---
> v2: add a comment that max pixel clock limit is a workaround
>
> drivers/video/rockchip/rk3328_hdmi.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/drivers/video/rockchip/rk3328_hdmi.c
> b/drivers/video/rockchip/rk3328_hdmi.c
> index 763669c09be..ff351aaac7c 100644
> --- a/drivers/video/rockchip/rk3328_hdmi.c
> +++ b/drivers/video/rockchip/rk3328_hdmi.c
> @@ -105,9 +105,20 @@ static int rk3328_hdmi_probe(struct udevice *dev)
>         return 0;
>  }
>
> +static bool rk3328_hdmi_mode_valid(struct udevice *dev,
> +                                  const struct display_timing *timing)
> +{
> +       /* Limit pixel clock to 297MHz. While RK3328 support higher rates
> and it
> +        * works in Linux, it doesn't seem to work in u-boot. That limits
> max
> +        * resolution to 1440p
> +        */
> +       return timing->pixelclock.typ <= 297000000;
> +}
> +
>  static const struct dm_display_ops rk3328_hdmi_ops = {
>         .read_edid = rk_hdmi_read_edid,
>         .enable = rk3328_hdmi_enable,
> +       .mode_valid = rk3328_hdmi_mode_valid,
>  };
>
>  static const struct udevice_id rk3328_hdmi_ids[] = {
> --
> 2.49.0
>
>